In a radio system, a receiver is usually used to demodulate a radio frequency (RF) signal that is received by an antenna and to generate a demodulated signal. The RF signal can be transmitted in the receiver by an in-phase channel and a quadrature-phase channel. However, the two channels may suffer from a phase imbalance, that is, a phase difference between the in-phase channel and the quadrature-phase channel may be relatively large. As a result, the demodulated signal output by the receiver may be distorted.
A detection scheme can be employed to detect the phase imbalance in the receiver. One of the detection schemes is to determine if the phase imbalance occurs based on the maximum likelihood criterion. However, such detection scheme may employ relatively complex computation.
Furthermore, a compensation circuit can be employed to adjust/compensate the phase imbalance. A conventional compensation circuit employs a voltage-controlled oscillator (VCO) or a voltage-controlled low pass filter (VCLPF) to continuously adjust the phase imbalance, and thus may result in relatively high power consumption. Furthermore, the VCO or the VCLPF consumes additional area, and thus the cost of such conventional compensation circuit may be increased.